/*******************************************************************************
 * Copyright 2020 huanggefan.cn
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/

package core

import (
	"log"
	"net/http"
	"net/http/pprof"
	"path"
)

const helpInfoFormatStr = `
---------------------------------------------------------------------
look at the heap profile:
go tool pprof '%s'
look at a 5-second CPU profile:
go tool pprof '%s'
look at the goroutine blocking profile:
go tool pprof '%s'
collect a 5-second execution trace:
wget '%s'
look at the holders of contended mutexes:
go tool pprof '%s'
view all available profiles:
open %s
---------------------------------------------------------------------
`

func StartPPOFDebug(server http.Server, showHelp bool) {
	var httpHandler = http.NewServeMux()
	var indexListen = path.Join(server.Addr, "/debug/pprof/")

	server.Handler = httpHandler

	httpHandler.HandleFunc("/debug/pprof/", pprof.Index)
	httpHandler.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
	httpHandler.HandleFunc("/debug/pprof/profile", pprof.Profile)
	httpHandler.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
	httpHandler.HandleFunc("/debug/pprof/trace", pprof.Trace)

	if showHelp {
		log.Printf(helpInfoFormatStr,
			indexListen+"/heap", indexListen+"/profile?seconds=5", indexListen+"/block",
			indexListen+"/trace?seconds=5", indexListen+"/mutex", "http://"+indexListen+"/",
		)
	}

	if err := server.ListenAndServe(); err != nil {
		log.Fatalln(err)
	}
}
